This is a transitional 22/32 kit gun, frame and barrel produced circa 1940. Then upgraded with post-war parts and shipped June 5, 1951, sent to an individual in New York state. One of a shipment of 25 that were similarly treated. Pretty rare, and in excellent original high-polish blue.
John
More about this particular gun here:
http://smith-wessonforum.com/members...2-kit-gun.html